Do You Need to Believe in Orbitals to Use Them?: Realism and the Autonomy of Chemistry

Abstract

Eric Scerri and other authors have acknowledged that the reality of chemical orbitals is not compatible with quantum mechanics. Recently, however, Scerri and Sharon Crasnow have argued that if chemists cannot consider orbitals as real entities, then chemistry is in danger of being reduced to physics. I argue that the question of the existence of orbitals is best viewed as an issue of approximation, not metaphysics: in many chemically important cases orbitals do not make sufficiently accurate predictions, and must be replaced. Chemists and physicists can acknowledge this fact while maintaining the utility of orbitals and the autonomy of chemistry.